'Sharp increase' in Covid cases after events in north Down and east Belfast
Social events in North Down and East Belfast have resulted in a "sharp increase" in Covid-19 cases, the Public Health Agency has said.
It described the surge in infections as emanating from a number of events in those areas attended by young people last week.
The PHA also warned that more cases are "likely to follow in the next few weeks" in South Belfast, Hillsborough, Comber, Bangor and the Ards Peninsula through previous and new social links.
The PHA said it is investigating the circumstances and deploying control measures.
It comes as the Department of Health announced no further deaths in its daily update.
Meanwhile, 278 positive cases of the virus have also been recorded since Monday - including 22 cases across the Ards and North Down Borough Council area and 28 across Belfast.
Head of health protection Dr Gerry Waldron urged the public to exercise caution to help limit the spread of the virus.
"Unfortunately, we have in recent days seen an increase in cases in the younger age group," he said.
"This is a group which is less likely to have received both doses of the vaccine and, with the increasing number of Delta cases in Northern Ireland, which we know to be much more transmissible, we are urging everyone to be sensible, enjoy the summer months, but do so safely.
"Over the next few days there will be temptation to get out and enjoy the warm weather and celebrate, but if we see large numbers gathering or people abandoning public health advice, we could see a sharp increase in cases, so we all need to act with caution."
The PHA also encouraged all over-18s to get vaccinated against Covid-19.
Chief Medical Officer Sir Michael McBride reiterated that Covid-19 remains a "real threat".
"All of us have made great sacrifices to keep each other safe during the pandemic and I am very much aware of the impact of the restrictions on young people. They've lost out on so much and they deserve to be able to enjoy the summer with their friends and families," he said.
"Our advice remains the same - stick to guidelines and regulations; all adults aged 18 and over should get vaccinated; and, in particular, ensure you and your close contacts self-isolate if you test positive.
"I would also appeal to those organising or attending events, and to the venues hosting groups of people, to follow the current regulations and public health guidance."